Breast cancer is an increasingly important cause of illness and death among women. In recent years several novel prognostic determinants of breast cancer have been identified which includes p53. Alterations of p53 are one of the most common abnormalities detected in primary breast cancer. In this study alteration of p53 in primary carcinoma breast was correlated with other pathological variables and disease outcome. In this prospective study the expression of p53 oncoprotein was analyzed immunohistochemically on 315 patient's tumour specimens of infiltrating ductal carcinoma of breast from 1992 to 1997. These patients also had axillary lymph nodes sampling. Both univariate and multivariate statistical analysis was performed to analyze results including disease outcome. Overexpression of p53 was observed in 55.23% tumours. Axillary lymph node metastasis had significant correlation with positivity of p53 (p<0.05). A significant number of p53 patients developed local recurrence and distant metastases to brain, liver, lung and bone (p< 0.05). At a median follow-up of 48 months (4 years) in p53 positive patients, the median overall survival (OS) was 3.0 years and disease free survival (DFS) was 2.5 years. p53 negative tumour patients showed a better survival. In this group the median OS was 3.8 years and the DFS was 3.3 years. The above findings have reinforced the view that p53 immunohistochemical detection is of help in detecting a subgroup of breast carcinoma patients who are at high risk. This may also be of particular relevance in decisions regarding adjuvant chemotherapy to these patients.